I think that what it actually means is that a bunch of people who supposedly violated some arbitrary limit on the limit of a specific substance in their bloodstream might have their lives un-ruined.
Well, I for one would prefer that somebody go through the system over what is about to happen. This sets a foundation for all other cases. This will be the new out for anyone who gets arrested for DUI. You get arrested and blow a .550 (should be dead but let's overlook that)and you attorney says "I want source code". It is now either give it up or go free. Coming from a state where the defense will try any and every trick, any normal the more obsurd the better it works, to get a client off the hook, I am not looking forward to giving them an easy out. Our system may not be perfect but hey, it is a far cry better then no system.
Is this going to matter for the people who were obviously intoxicated? No. This is going to matter for the people who passed a field sobriety test, didn't appear to be intoxicated, but admitted to having a beer that night and were required to take a breathalyser.
Wrong. This will matter for ALL cases. By getting the Breath Test results tossed, you now lose the proof of Alcoholic Beverages being involved. Basically, no breath test = no proof of intoxication unless a blood or urine sample was taken. No blood or urine sample = no proof of drug related issues. Case dismissed unless somebody is rather lucky.
...did you use mouthwash before heading out tonight?
They had better have been stopped withing 90 seconds of that usage. The residual ethanol in the mouth would have evaporated. Just like if you burp up something while taking the breath test, the instrument will detect the spike in Ethanol and let you know it was an invalid sample.
As for how to prevent DUIs in the first place, you have some valid suggestions but a lot would change if more responsibility was placed on the establishments who serve the drinks. They have a moral obligation to cut you off after your 15th beer. But screw morals, 1 more $5 beer won't hurt anyone.